Submersible pumping systems are often deployed into wells to recover petroleum fluids from subterranean reservoirs. The submersible pumping system includes one or more fluid filled electric motors coupled to one or more high performance pumps. When energized, the motor provides torque to the pump through a series of connected shafts. When rotated, the pump pushes wellbore fluids to the surface through production tubing in accordance with well-known fluid mechanics.
During operation, thrust generated by the pump is carried through the shaft to other components within the pumping system. Because the components within the pumping system are often closely positioned with very small tolerances, axial movement created by thrust from the motor or pump may cause adjacent components to come into contact. This contact may accelerate wear or cause immediate damage to the components within the pumping system.
In the past, designers have employed interference-based thrust bearings to carry the thrust created within the pumping system. Typical thrust bearings include a stationary portion affixed to a housing, a rotating portion affixed to the rotating shaft, and a pad positioned between these two portions. The pad resists axial motion between the stationary and rotating portions of the thrust bearing.
Although widely adopted, the use of traditional thrust bearings may be undesirable in certain applications. Because traditional thrust bearings require contact between the rotating and stationary portions of the thrust bearing, the components within the thrust bearing must be installed within prescribed tolerances. Additionally, as the thrust pads wear over time, the tolerances between adjacent components may change and the thrust bearing may become less effective at limiting axial movement along the shaft. There is, therefore, a need for an improved thrust bearing design that overcomes these and other deficiencies in the prior art.